Myxer has launched a music app for BlackBerry that claims a catalog of more than 2 million MP3s. The app joins a long list of music apps for BlackBerry such as Pandora, Slacker Radio, Thumbplay Music, Music WithMe, etc. With so many music apps out there, guys like Myxer and Thumbplay need to offer more than just an MP3 database. The best music apps build an experience around your music. Slacker Radio gives you a cool radio-style way of discovering music and Pandora tries to learn what you like with a Genius-style algorithm. Users want cool new ways of discovering music and not just another database of relatively expensive music.